In a cellular wireless telecommunications system, radio coverage is provided by areas known as cells. A base station is located in each cell to provide the radio coverage area. Traditional base stations provide coverage in relatively large geographical areas and these cells are often referred to as macro cells. It is possible to provide smaller-sized cells, often within a macro cell. Such smaller-sized cells are sometimes referred to as micro cells, pico cells or femto cells. The term femto cells will be used to refer generally to all such small cells. Small cells are typically established by providing a small-cell base station that provides radio coverage having a relatively limited range within the radio coverage area of a macro cell. The transmission power of the small-cell base station is relatively low and, hence, each small cell provides a smaller coverage area compared to that of a macro cell and covers, for example, an office or a home. A group of such small-cell base stations may together provide a wireless small-cell network.
Such small cells are typically provided where the communications coverage provided by the macro cell is poor or where a user wishes to use an alternative communications link provided locally, by the small-cell base station, to communicate with the core network. Such a situation may arise where, for example, a user has a pre-existing communications network and the user wishes to utilise that link in preference to that provided by the macro network to communicate with the core network. The group of small-cell base stations providing the wireless small-cell network can together provide extended local coverage to user equipment throughout, for example, a home or an office building by using multiple small-cell base stations distributed throughout those buildings which enables each of those base stations to transmit at a lower power than would otherwise be necessary if coverage was provided by a single small-cell base station.
However, the proliferation of the deployment of such small-cell base stations, as well as any increasing density in macro base stations, can cause undesirable consequences. Accordingly, it is desired to provide improved techniques for obviating the problems associated with such deployment.